| In order to degrade the macromolecular protein of soybean meal to soybean peptide, casein-plate method
was adopted as a screening model in this study. Firstly, high protease-producing strains were isolated and screened from
soil, and the strains possessed bigger ratio of hydrolytic circle and colony diameter were selected. After liquid fermentation,
protease activity and peptide conversion rate of the strain were measured. Finally, strain B1 was chosen with 111.8 U/mL in
enzyme activity and 37.2% in peptide conversion rate. Judged by morphological, physiological and biochemical
characteristics, the strain was identified as Bacillus sp. |
