关键词: 鲫鱼鱼鳞, 抗菌肽, 分离纯化, 抑菌活性

Abstract: Antimicrobial hydrolysate was obtained from crucian carp scales by citric acid extraction and enzymatic hydrolysis after pretreatment. Then after dialysis, the hydrolysate was separated and purified successively by Sephadex G-15, Sephadex G-50 gel filtration and cellulose DEAE-52 anion exchange chromatography, yielding peptides with strong antimicrobial activity. The molecular mass, antimicrobial activity and minimal inhibitory concentration (MIC) against various bacteria and fungi of the purified antimicrobial peptide were determined. The results showed that AcIII, a purified protein with antibacterial activity, was obtained. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed a single band, indicating that AcIII was electrophoretically pure. Its molecular mass was about 20.1 kDa. AcIII showed that crucian carp scale antimicrobial peptide had strong and broad-spectrum antimicrobial activity. The MIC against Staphylococcus aureus, Bacillus subtilis, Staphylococcus albus, Vibrio parahaemolyticus, Pseudomonas fluorescens and Shewanella putrefaciens were 16 μg/mL while the MIC against Escherichia coli and Salmonella choleraesuis were 32 μg/mL.

Key words: crucian carp scale, antimicrobial peptides, isolation and purification, antimicrobial activity