Abstract:The aim of the study was to analyze the bacteria composition of the traditional fermented cheese-milk knot in Xinjiang and the effect of the fermented probiotics on the physiological function and gene expression associated with senescence of Caenorhabditis elegans to explore the mechanism of its anti-aging effect. High throughput sequencing method and biostatistics method were used to analyze the composition and regulation information and the results showed that the dominant bacterial groups were mainly Lactobacillus, Pseudomonas, Streptococcus, Lactococcus and Lactobacillus is the dominant bacterium in the other four samples except RS1.1 samples. Lactobacillus rhamnosus R4, an acid-resistant and bile tolerant probiotic with life-extending effect, was isolated. Transcriptome sequencing showed that L. rhamnosus R4 stimulated the key enzyme coding genes in the insulin signaling pathway. L. rhamnosus R4 significantly increased the transcription levels of sod-3, hsp-16.2, ctl-1, and daf-16, while the expression levels of daf-2 and sir-2.1 were significantly down-regulated, suggesting that their effects on longevity of nematodes depend on insulin signaling pathway.