Effects Of Staple Diet Swap On The Gut Microbiota Structure And Function Of Mongolian Volunteers

Food is of paramount importance to people.Diet is not only an indispensable part of daily life,but an important factor that affects the gut microbiota.By improving the colonic environment,it will be possible to change the gut microbiota compostion,which helps improve the host health and prevent from diseases.The ingestion of a reasonably healthy diet is one economic way to modulate the gut microbiota.In recent years,much research has focused on investigating the effect of gut microbiota modulation in relation to host health.However,only limited studies have analyzed the association between the staple diet intake and gut microbiota in China.Therefore,it is meaningful to explore such aspect in this study.This study simulated the properties of common types of diet in China.We selected the representative Chinese diet and the unique Mongolian diet.We conducted a trial of staple diet sway for three weeks in Mongolian volunteers.During the staple diet swap was done every 7 days for the three weeks.The diets for the first,second,and third week were principally composed of wheat,rice,and naked oats,respectively.The effects of dietary intervention on the structure and function of intestinal microbiota was studied by using the PacBio SMRT and shotgun genome sequencing technology by the Illumina Hiseq sequencing platform.The results are as follows:The PacBio SMRT sequencing results showed that Firmicutes,Bacteroidetes,Tenericutes,and Proteobacteria were the main phyla of the volunteers' intestinal microbiota.At the family level,the individual differences of volunteers' intestinal microflora were obvious.The dietary intervention of wheat flour,rice,and naked oats affected the intestinal microbiota structure of the Mongolian volunteers.The abundance and diversity of intestinal microbiota decreased consistently.Moreover,a significant effect was seen in individuals who were rich in Bacteroidaceae within the gut microbiota.Subject to the dietary intervention,the abundance of bacteria associated with carbohydrate-and butyrate-associated metabolic pathways varied significantly.The abundance of Ruminococcusa?albus was 4.06-fold higher when naked oak was given compared with wheat-based meal.The abundance of Bacteroides fragilis and Roseburia were 5-and 4.04-fold higher than that of before diet intervention.Results from the shotgun genome sequencing showed that the three-week dietary intervention could change the structure and function of intestinal flora of the subjects rapidly.A strong concordance was found between the gastrointestinal bacterial microbiome and the intestinal virome.Wheat and oat favored bifidobacteria(Bifidobacterium catenulatum,Bifodobacterium bifidum,and Bifidobacterium adolescentis)compared with rice-based diet.Significant effects were seen also on the function and metabolic pathways of the intestinal microbiota of the volunteers during the diet intervention.The carbon metabolism pathway genes were enriched during the three weeks.Correlations were found between Lactobacillus ruminis and sialidase,as well as Butyrivibrio crossotus and xvlanase/xylosidase.It is the first time to study the effects of dietary intervention on the structure and function of intestinal microbiota was studied by using the PacBio SMRT and shotgun genome sequencing technology by the Illumina Hiseq sequencing platform.By integrating two sequencing techniques,this study investigated the effects of staple diet swap,particularly changes in the diet carbohydrate content,on the gut microbiota.The present study has gained novel insights into health maintenance,and provides a theoretical basis for further study of the formation of the intestinal microflora and the optimization of diet structure of Chinese people.