鲫鱼鱼鳞抗菌多肽的制备纯化及其抑菌活性

以鲫鱼鱼鳞为原料,对其预处理后采用柠檬酸浸提酶解等工艺得到鱼鳞抗菌多肽粗酶解液,经透析后,再依次经Sephadex G-15、Sephadex G-50凝胶过滤层析和纤维素DEAE-52阴离子交换层析对其进行分离纯化,最后得到具有较强抑菌活性的鲫鱼鱼鳞抗菌多肽,并对其进行分子质量分析以及对多种细菌、霉菌的抑菌活性和最小抑菌浓度(minimal inhibitory concentration,MIC)测定。结果表明:经分离纯化后得到的具有抑菌活性的蛋白组分AcIII,十二烷基硫酸钠-聚丙烯酰胺凝胶电泳结果显示为单一条带,表明其已达到电泳级纯,其分子质量约为20.1 kDa,抑菌活性测定结果表明鲫鱼鱼鳞抗菌多肽具有很好的广谱抗菌活性,对金黄色葡萄球菌、枯草芽孢杆菌、白色葡萄球菌、副溶血性弧菌、假单胞菌和希瓦氏菌的MIC为16μg/mL,对大肠杆菌和沙门氏菌的MIC为32μg/mL。

Preparation,Purification and Antimicrobial Activity of Antimicrobial Peptide from Crucian Carp Scales

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.