Effects of Different Preparation Methods on Microbiota Composition of Fecal Suspension.

Fecal microbiota transplantation is an emerging disease-modifying therapy. The viability of the microbiome in feces and its successful transfer depends on the preparation of fecal microbiota suspension. However, currently, no standard operation procedure is proposed for fecal suspension preparation. This study aims to compare the effect of different preparation methods on the composition of fecal microbiota composition in the rat. Four methods were used to collect the fecal suspension from fresh rat fecal (Group A), including stirring with normal saline (Group B), stirring with normal saline and then standing (Group C), stirring with normal saline and filtered with gauze (Group D), and stirring with normal saline and centrifuged (Group E). 16S ribosomal RNA gene (16S rDNA) sequencing technology was used to analyze the microbiota diversity and composition of each group of samples. Compared with fresh feces, the bacterial richness of the fecal suspension obtained by the four methods was significantly decreased (P < 0.05). The structural similarity with fresh fecal microbiota from high to low is groups B, D, C, and E. All four methods changed the microbiota structure to varying degrees, thus may affect the effect of FMT. In conclusion, choosing different methods to prepare fecal suspensions may help to better optimize the application of FMT.