Preparation of capsules.
STERILE, SEPARATION
Fresh stool was collected from donors in a sterile plastic container. The dry weight of the stool needed to be more than 100 g. Fresh fecal samples (25%) were mixed with saline (60%) and pharmaceutical-grade glycerol (15%) in a semiautomatic extraction instrument (Treatgut TG-01; Anjiezhishan Company, China). The instrument was launched to start the process of gradual separation. After the extraction process was performed using sterile tubes, the supernatant was collected and centrifuged to obtain the precipitate containing fecal microbiota. The precipitate was mixed thoroughly, and the capsules (DrCaps; 19504907) were filled. Each capsule contained an average of 0.9 g of precipitate of fecal microbiota and was immediately frozen at −80°C.