SRP493800 PRJNA1085102 Study of microbial diversity on mice cecum contents Chronic stress is a major health concern in current society that often leads to various mental disorders, particularly anxiety and depression. In recent years, increasing evidence has demonstrated that an imbalance in the microbiota-gut-brain axis plays an important role in the pathogenesis of anxiety and depression. The intake of certain probiotics and prebiotics, has been implicated in improving mood disorders through the microbiota-gut-brain axis. In addition, although not directly exposed to light, the gut microbiota follows daily fluctuations in composition and function, and their regulation is controlled by the host feeding rhythms. Specific microbial taxa and key microbially derived metabolites, exhibit wide oscillations over a 24-h period. These findings suggested that intake time may affect the function of prebiotics; however, the impact of different administration times on intervention effectiveness has been overlooked in many studies. In our study, CUMS-induced mouse model and fecal bacteria transplantation combined with 16S rRNA sequencing were applied to investigate the influence of microbiota on the anxiolytic and antidepressant ability of inulin. Through the detection of intestinal microbial diversity and composition of mice in each group, the role of intestinal microbes in the relief of anxiety- and depression-like behaviors of mice by inulin treatment was explored, and the different effects of different intervention times of inulin on intestinal microbes were obtained.