解淀粉芽孢杆菌KN-BL-1及其发酵豆粕产抗菌肽类物质的研究

以牛津杯法比较解淀粉芽孢杆菌KN-BL-1及其发酵豆粕的抑菌效果,通过酸沉淀法分离粗多肽,确定产生抑菌效果的为多肽类物质,通过DEAE-Sepharose离子交换层析及Sephadex G-25凝胶过滤层析分离纯化粗多肽以研究其各组分的抑菌效果,并使用4000 Q TRAP液相色谱-质谱联用仪初步确定抗菌肽样品的分子量范围.结果表明,KN-BL-1及其发酵豆粕浸提液对S.aureus等革兰氏阳性菌均有明显的抑菌效果;粗多肽经过层析分离纯化后,三个峰表现抑菌特性,其中有一个抑菌效果最好,抑菌圈清晰,直径为19.8 mm.

Study of the Antibacterial Peptides Produced by Bacillus amyloliquefaciens KN-BL-1 and Its Fermented Soybean Meal

The inhibitory effect of Bacillus amyloliquefaciens KN-BL-1 and its fermented soybean meal were compared by oxford cup method. The crude peptides which separated by acid-precipitation were determined as the effective antibacterial ingredients. In order to study the inhibitory effect of each component of the crude peptides, DEAE-Sepharose ion exchange chromatography and Sephadex G-25 gel filtration chromatography methods were used to separate the crude peptides and the molecular weight of the antibacterial peptides were initially identified by 4000 Q TRAP HPLC-MS. The results showed that the KN-BL-1 and its fermented soybean meal had a significant inhibitory effect to S.aureus and other Gram-positive bacteria. After separated and purified through chromatography, three elution peaks showed antibacterial properties.one of the three had the strongest inhibitory effect, and its diameter of antibiotic circle was 19.8 mm.