Abstract:

In order to substitute the widespread use of antibiotics to prevent from pathogen resistance, we greatly enhanced the development of casein antimicrobial peptides. We hydrolyzed casein using neutral protease and based on neutral protease concentration, hydrolysis time, hydrolysis temperature and pH viewed as influence factors. We used single factor experiments and centure-composite design center combination method of four factors and three levels experimental design to further optimize hydrolysis condition. The results showed that the effect of enzyme concentration, hydrolysis time, hydrolysis temperature and pH were significant. The conditions of casein antibacterial peptide preparation were optimized as following: enzyme concentration 3.73%, hydrolysis temperature 50℃, pH 7.9 and time 130 min. Regression equations predicting casein hydrolysate antibacterial ring diameter could reached 21.93 mm, the average degree of antibacterial ring diameter of three experiments could reached 21.91 mm, which was close to the theoretical maximum, showing that the model could predicted the optimal conditions of casein antibacterial peptide preparation.