关键词: 便秘, 肠道细菌, 合生元, 基因

Abstract: Background　Chronic functional constipation is a common clinical intestinal disease.At present，more and more evidences indicate that microbial treatments have a positive clinical efficacy，but it need to be further explored that how it changes the intestinal microenvironment.Objective　To further explore the roles of particular species of gut microbiota in chronic functional constipation（CFC） and their responses to treatment with synbiotics based on our previous studies.Methods　This study was conducted from July 2016 to March 2017 between the constipation group（6 cases of CFC selected from the 24 participants of our previous studies） and the healthy group（6 controls sampled from the healthy community-dwelling individuals）．Fresh fecal samples were collected with the stool sample collection kit from the constipation patients before and after the treatment with synbiotics and from the controls.All samples were transported with ice and stored in - 80 ℃ refrigerator in laboratory，and analyzed with the metagenomic detection.The abundance of the detected particular species of gut microbiota was analyzed comparatively and their roles were interpreted.Results　A total of 10 species of Bifidobacterium were detected.Compared with the healthy group，the constipation group demonstrated much higher abundance of Bifidobacterium dentium，Bifidobacterium adolescentis and Bifidobacterium animalis before receiving the treatment（P<0.05）．Bifidobacterium animalis increased significantly in the constipation group after treatment（P<0.05）．Totaled 38 species of Lactobacilli were identified.The constipation group showed much lower abundance of both Lactobacillus oris and Lactobacillus reuteri before receiving treatment than the healthy group（P<0.05）．After treatment，the constipation group presented obviously enhanced abundance of Lactobacillus oris（P<0.05）．Moreover，the abundance of Escherichia coli，a species of Escherichia，declined significantly in the constipation group after treatment（P<0.05）．The constipation group demonstrated much lower abundance of 6 species of Prevotella before treatment compared with the healthy group（P<0.05）．Genes of these gut microbiota mainly involve in carbohydrate metabolism.PCoA analysis showed that the distribution of genes of gut microbiota in CFC patients was significantly different from that of the healthy controls，moreover，it showed little changes in the CFC patients after treated by synbiotics.Conclusion　The particular species of gut microbiota in CFC patients were significantly different from those of the healthy people.The treatment with synbiotics plays a positive role in treating CFC might be via improving the metabolic environment of the gut microbiota，for the abundance of the traditional probiotics showed little responses to the treatment.

Key words: Constipation, Enteric bacteria, Intestinal microbial, Gene