关键词: 苦荞蛋白, 酶解, 抗菌肽, Plackett-Burman试验, Box-Behnken试验

Abstract: The enzymatic hydrolysis of tartary buckwheat protein with neutral protease to produce antibacterial peptides was optimized using Plackett-Burman and Box-Behnken designs. One-factor-at-a-time experiments were carried out to investigate the effect of substrate concentration, enzyme-to-substrate ratio, pH, hydrolysis temperature and time on the antibacterial activity and peptide concentration of hydrolysates. The factors with a significant influence on the response variables were selected using Plackett-Burman design and optimized for maximum peptide concentration using Box-Behnken design. The optimum parameters for enzymatic hydrolysis were determined as follows: substrate concentration 3.22%, enzyme-to-substrate ratio 4 000 U/g and pH 6.86. Under these conditions, the peptide concentration was 32.41 mg/mL, in good agreement with the predicted value (32.12 mg/mL), and the percentage inhibition of antimicrobial peptides was (27.88 ± 2.78)% against E. coli and (94.56 ± 0.74)% against S. aureus. In conclusion, this optimized procedure was reasonable.

Key words: tartary buckwheat protein, enzymatic hydrolysis, antibacterial peptides, Plackett-Burman design, Box-Behnken design