枯草芽孢杆菌WL17产抗菌物质的分离、分析及其抗菌特性研究

Isolation,Analysis and Properties of Antibacterial Substance Produced by Bacillus Subtilis WL17

用盐酸沉淀枯草芽孢杆菌WL17发酵液,用甲醇抽提得粗提物。采用Sephadex LH-20柱分离粗提物,经HPLC分析,抗菌物质可能为1组由多种分子质量组成的肽类物质。该抗菌物质对鼠伤寒沙门氏菌、金黄色葡萄球菌等食品病原菌有显著的抑菌作用;对pH、温度以及胃蛋白酶、胰蛋白酶不敏感,但在高温、强酸或强碱共同作用下,抗菌物质的抑菌能力显著降低;抗菌物质在不同时间的脉冲强光照射下,稳定性未发生显著变化。

The crude extract was obtained from fermented broth of Bacillus subtilis WL17 by acid sediment and methanol extraction.And then separated with Sephadex LH-20 column,HPLC analysis showed that antibacterial substance may be a group of antibacterial peptides with different molecular weights.The antibacterial substances showed significant antagonistic activities against many food pathogens,such as Salmonella typhimurium,S.aureus and so on.The antibacterial substances were very stable against high temperature pH,trypsin and pepsin.But under the treatments of high temperature and strong acid or strong base,the antibacterial activity decreased significantly.In addition,the antibacterial substances were stable against pulsed light treatment.