Studies on alkaline protease from Bacillus licheniformis II Purification and some properties of alkaline protease

The alkaline protease produced by Bacillus licheniformis strain JF 1d was partially purified through the process involving ammonium sulfate precipitation, Sephadex G 100 filtration, and the final product was obtained. The specific activty of enzyme was increased from 1878 U/mg to 6795 U/mg with the recovery of 35.3%. The optimal temperature and pH for casein hydrolysis were 55℃ and 10.5 respectively. The enzyme was stable within the pH range from 7 to 12 and it has strongly endurance towards SDS.