The invention discloses a method for purifying C21 steroidal
glycoside in
fermentation broth, which belongs to the technical field of substance purification, and comprises the following steps: taking radix cynanchi bungei
endophyte with C21 steroidal
glycoside synthesis capability as a
fermentation strain, and inoculating the
fermentation strain to an LB culture medium or a Gause No.1 culture medium for activation; then transferring into a fermentation culture medium and culturing to a
secondary metabolism period; centrifuging the fermentation liquor at 10,000 rpm for 5 minutes, collecting supernate,
drying to obtain a precipitate, adding absolute ethyl
alcohol, uniformly mixing, standing for 10 minutes, centrifuging, and collecting supernate
alcohol extract; adding the
alcohol extract into a precipitating agent according to a volume ratio of 1: (1-7), oscillating and uniformly mixing, standing overnight, centrifuging, and collecting a precipitate; and the precipitate is dried, such that the C21 steroidal
glycoside is obtained. The method does not need to depend on
plant resources, is high in
sustainability,
repeatability and stability, is suitable for large-scale production, and has important significance in the technical field of purified substances and the field of medicines.