Abstract:Response surface methodology was used to optimize the components of fermentation medium and the fermentation conditions affecting the exopolysaccharides (EPS) production of Weisssella cinerea SJ-02. Taking EPS production as an index, the effects of carbon sources and nitrogen sources in the medium on the yield of exopolysaccharides were explored. The results showed that using MRS as basal medium, keeping its 2% glucose and replacing peptone with 1.5% soy peptone increased the EPS production of strain SJ-02. The Box-Behnken central combination design was used to study the effects of exopolysaccharides production. The optimal fermentation conditions were as follows: inoculation amount 3.00%, fermentation time 34 h, fermentation temperature 37 ℃. Under these conditions, the theoretical prediction of EPS production is 335.03 mg/L, and the production of EPS by verification test is 331.47 mg/L, which is 17% higher than before.