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

摘要： 背景　慢性功能性便秘是一种临床常见的肠道疾病，目前越来越多的证据显示采用微生态制剂治疗慢性功能性便秘具有积极的临床疗效，但其对肠道菌群环境的改变作用还有待进一步探索。目的　在前期研究基础上进一步探讨合生元对慢性功能性便秘患者肠道特定菌群的影响，并对肠道特定菌群的功能进行注释。方法　2016年7月—2017年3月，从前期研究确定的24例研究对象中最终筛选出6例患者（便秘组）进入本研究，同时在社区招募6例健康人进入健康组，用大便盒分别留取便秘组患者合生元治疗前后及健康组的新鲜粪便样本，与冰块一起运送至实验室并存放于-80 ℃冰箱，进行粪便菌群宏基因组检测，比较特定菌群的丰度水平并进行功能注释。结果　10种双歧杆菌在种水平被检出，其中健康组B.dentium丰度水平高于便秘组治疗前，便秘组治疗前B.adolescentis、B.animalis丰度水平高于健康组（P<0.05）；便秘组治疗后B.animalis丰度水平较便秘组治疗前增高（P<0.05）。38种乳酸杆菌被检出，其中健康组L.oris、L.reuteri丰度水平高于便秘组治疗前（P<0.05）；便秘组治疗后L.oris丰度水平较治疗前增高（P<0.05）。埃希菌属中的Escherichia_coli经过治疗后丰度水平下降（P<0.05），健康组普氏菌属（Prevotella）中有6种菌群的丰度水平高于便秘组治疗前（P<0.05）。肠道菌群基因主要参与碳水化合物的代谢，主成分分析发现便秘组与健康组肠道菌群基因分布有明显差异，而便秘组治疗前后变化不明显。结论　慢性功能性便秘患者中肠道特定菌群存在差异，合生元治疗对传统益生菌的丰度水平改变并不明显，其可能通过改变肠道菌群的代谢环境而发挥作用。

关键词: 便秘, 肠道细菌, 合生元, 基因