method for producing Dianemycin 1-sodium salt using *Streptomyces nanchangensis* fermentation includes spore culture, seed tank culture, fermenter culture, and extraction steps:
1) *Streptomyces nanchangensis* preserved in sand tubes are inoculated onto Gao's medium or bran agar medium for scale-up culture for 10-20 days;
2) *Streptomyces nanchangensis* spores obtained in step 1) are inoculated into a seed tank containing the seed medium designed in this invention and equipped with a stirring device for fermentation culture. The fermentation culture conditions are: temperature: 25-35℃; aeration rate: 1:0.5-1:1.5V/V; stirring speed: 200-600 rpm; culture time: 36-60 hours.
3) The culture obtained in step 2) is further inoculated into a fermenter containing the culture medium designed in this invention and equipped with a stirring device for fermentation culture. The fermentation culture conditions are: inoculum size 5-20% V/V; temperature 25-35℃; aeration rate 1:0.5-1.5 V/V; stirring speed 200-600 rpm; fermentation time 90-140 hours. Multiple intermediate feedings can be made during fermentation in the fermenter, and the fermentation time is 120-230 hours in this case;
4) The fermentation liquid obtained in step 3) is filtered to obtain filtrate and filter cake;
5) The filter cake is extracted with methanol, ethanol, chloroform, dichloromethane, acetone or benzene to obtain an extract;
6) The extract is concentrated, and then the concentrated extract is extracted with ethyl acetate or butyl acetate to obtain an oily substance;
7) The oily substance is absorbed with excipients, dried, ground into powder, and the Dianemycin 1-sodium salt preparation is obtained.
