Abstract:

This work reports the preparation of antibacterial peptide by enzymatic hydrolysis of prickly ash seed protein
with acid protease. Substrate concentration, enzyme/substrate ratio, pH, hydrolysis temperature and hydrolysis time were
investigated by single factor method for their effect on the anti-E. coli activity of hydrolysates. Optimization of enzyme/
substrate ratio, hydrolysis temperature and hydrolysis time based on anti-E. coli activity of hydrolysates was carried out using
a Box-Behnken experimental design. The degree of hydrolysis of prickly ash seed protein was 9.05% and the inhibitory rate
of the produced antibacterial peptide against E. coli was 56.98% when the hydrolysis experiment was carried out for 4.7 h
at 51.2 ℃ and an initial pH of 4.0 with a substrate concentration of 30 mg/mL and an enzyme/substrate ratio of 3.0%.

Key words: prickly ash seed protein, antibacterial peptide, acid protease, inhibitory rate