Abstract:In order to obtain a higher yield of bacteriostatic peptides from Flammulina velutipes，this paper optimized the process conditions for preparing bacteriostatic peptides by solid-state fermentation of probiotics on F.velutipes，and used ultrafiltration to grade and compare the activity of bacteriostatic peptides. Using F. velutipes as the fermentation substrate，with the antimicrobial activity of the bacteriostatic peptides against Escherichia coli，Staphylococcus aureus，and Salmonella as the indicator，three probiotics including Bacillus subtilis，Saccharomyces cerevisiae and Aspergillus niger were screened，and the optimal pH value for separating and precipitating bacteriostatic peptides was selected. Then，the effects of four factors including liquid-to-solid ratio，fermentation time，fermentation temperature，and amount of F. velutipes on the yield of F. velutipes bacteriostatic peptides were investigated by single-factor and response surface experiments. The results showed that A. niger was the optimal strain for solid-state fermentation to produce F. velutipes bacteriostatic peptides. The optimal pH for precipitating bacteriostatic peptides was 4；the optimal fermentation conditions were as follows: liquidto-solid ratio of 3.5∶1（mL/g），fermentation time of 109.6 h，fermentation temperature of 28 ℃，and amount of F.velutipes of 27.21 g. Under these conditions，the yield of F. velutipes bacteriostatic peptides was（61.25±1.14）%.Bacteriostatic peptides with a molecular weight less than 3 kDa had the strongest activity.